This invention relates to the manufacture of thermoplastics pipe. It is particularly concerned with the manufacture of pipe by the radial expansion of a pipe blank by means of internal pressure.
Our British patent specification No. 1,432,539 discloses a method of forming at least part of a pipe of thermoplastics polymeric material within a female mould, by heating said part to a temperature at which deformation of the material induces orientation if the polymer molecules, and subsequently applying internal pressure to said part to force out said part of the pipe radially against the female mould. The pipe may include a socket portion of enlarged diameter, and the female mould may be designed to form this socket portion.
The present invention is concerned with improved apparatus for putting the previously described method into effect.